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The processing on CNC machines of parts of a complex profile with multipass shaping schemes is accompanied by multiple changes in the direction of movement of the working bodies (reverse) during the cutting process and at idle running. When reverse, loss of information is possible due to the presence of gaps in the chain of feed drive and elastic deformations determined by constant loads overcome by the drive. Permanent loads consist of cutting forces and friction in the feed drive chain. Information loss is defined as a position insensitive zone at a position. To determine the insensitive zone, a technique is proposed that takes into account the differential accounting of friction losses in the mechanical feed drive chain. To estimate the elastic deformations in the drive chain, design schemes are proposed and analytical dependencies obtained. Differentiated consideration of friction in determining the insensitive zone allows you to outline the main ways to improve feed drives. It is shown that the magnitude of the preload on the thrust bearings and the tensile forces of the lead screw during assembly do not have a significant effect on the size of the insensitive zone. Even less impact on the dead zone has a preload change in the transfer screw-nut rolling. It was determined that the main ways to reduce the insensitivity zone is to increase the rigidity of the screw-and-nut rolling transmission anchor to the machine carriage and reduce friction in the guides. In addition, an analysis of the layout decisions of the lead screw assembly (one-sided and two-sided termination) according to the insensitive zone criterion showed that the use of one-sided termination of the lead screw is more rational.

Based on the use of the electrothermal analogy in describing the heat transfer process, an engineering technique has been developed to determine the thermal state of the supports of spindle assemblies, which does not require “heavy” software packages based on the application of the finite element method. The design features of modern control rooms made it possible to reasonably present the thermal model in the form of a flat model. The principles of dividing the blocks of a flat model into enlarged elements are proposed, taking into account the features of the geometry of the calculated structure and heat sources. A technique has been developed for determining the thermal resistance of an element of a calculated thermal model taking into account boundary conditions. The use of enlarged elements of the thermal model makes it easy to assess the influence of technological features of processing and assembly of individual structural parts on its thermal state. The presented methodology for developing a thermal model can be used to estimate stationary thermal processes of any axisymmetric structures with insignificant temperature variations.

Conducted experimental studies have shown the high efficiency of using continuous dressing and its varieties - cleaning during grinding. The conditions that ensure the minimum wear of the ruling and working circles for various processing conditions are determined. It is established that the minimum wear of the circles takes place at a relative speed of the working and ruling circles, close to zero. At the same time, the productivity of the dressing process and the processing efficiency are practically not reduced. It is shown that the greatest efficiency of continuous dressing takes place when grinding materials that are prone to adhesive setting with the components of the abrasive wheel. Recommendations are given on choosing the ligament and firmness of the ruling circles. The mechanisms of wear of the circles at various slip coefficients are established. Ensuring the angle of intersection between the circles, as a rule, increases the efficiency of the process, in addition, reduces vibration in the editing system. An increase in the angle of crossing over 10° increases the wear of the circles. The use of continuous cleaning reduces wear on the working circle and does not distort its macro profile. It was found that the ruling circles with an abrasive, which was created using the technology of self-propagating high-temperature synthesis (SHS), have greater wear resistance than circles of a similar characteristic from elbor, but inferior to diamond.